Double-faced radio detector element



April 20 1926. 1,581,649

A. LOPPACKER DOUBLE mcmi RADIO DETECTOR ELEMENT Filed Feb. 6. 1922 Patented Apr. 20, 1926.

UNITED STATES PATENT orFlCE- ALBERT LOPPACKER, OF BLOOMFIELD, NEW JERSEY, ASSIGNOB 0F ONE-HALF TO HIM- SELF AND ONE-HALF TO FRANK J. KENT, OF NEW YORK, N. Y.

DOUBLE-FACED RADIO DETECTOR ELEMENT.

Application filed February To all whom it may concern:

Be it known that I, ALBERT LOPPACKER, a citizen of the United States, residing at Bloomfield, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Double- Faced Radio Detector Elements, of which the following is a specification.

This invention relates to crystal detectors for radio-receiving apparatus, and has for an object to provide, as a new article of manufacture, a body of sensitive crystal, as for instance galena or fused silicon or the like, and having a sheath surrounding it in such a way that opposite faces may be presented to the detector needle.

A further object is to provide a doublefaced sheathed detector element which includes two different sensitive materials, as for instance galena and silicon, bound together by the sheath, and each constituting one of the two opposite effective surfaces of the element.

Other objects and aims of the invention more or less broad than those stated above, together with the advantages inherent, will be in part obr ious and in part specifically referred to in the course of the following description of the elements, combinations, arrangements of parts. and applications of principles constituting the invention; and the scope of protection contemplated will appear from the claims.

In the accompanying drawings, which are to be taken as part of this specification, and in which I have shown merely a preferred form of embodiment of invention,

Figure 1 is a perspective view of a doublefaced detector element;

Figure 2 is a vertical sectional view of the same; and

Figure 3 is a view similar to Figure 2, illustrating a modification- Referring to the numerals on the drawing, there is shown at 4 a sheath of metal, which is ordinarily cast around a piece of the desired sensitive material so as to form in effect a band around it, with inturned edge portions 5 and 6 taking over the ope, 1922. Serial no. 534,431.

posed edge portions of the opposite working faces of the crystal or material 7, leaving the larger portions of the opposite faces exposed. The method of applying the sheath or holder is no part of the present invention, nor is the material ofthe sheath or holder, but as I have already stated, the crystal 7 may be of galena, for instance, and the sheath or holder of some metal having a low melting point. At any rate, the finished article should present two crystal surfaces, so that if for any reason one surface should not give satisfactory results when the detector needle is applied to it. the other surface may be utilized. I prefer that the complete article shall 'be'symmetrical and regular, so that in cases where it is fitted lnto a holder or seat member, it may be put in at will either right side up or upside down. In other Words, the article is double-faced, and in vertical section has uniform overall height and width.

In Figure 3 the structure is as shown in the other figures, except that there are two pieces of crystal or sensitive material. say galena and silicon, indicated at 9 and 10, held inback to back relation in the sheath and presenting their respective faces at the top and bottom of the article.

I claim: 7 v

1. A detector element having side walls, and substantially parallel top and bottom surfaces, the latter constituting the working faces of the element, and a sheath covering the side walls and portions only of both the top and bottom surfaces, so that either the top or the bottom surface of the element may be presented to a detector point.

The device set forth in claim 1, in which the sheathed element comprises two bodies of different materials, in bacl:-to-back relation, with their faces exposed.

3. A detector element comprising a supporting body of fusible metal having opposite faces provided with exposed rectifying surfaces.

4. A detector element comprising a main bedded therein as to provide rectifying surfaces in opposite faces thereof,

5. A detector element consisting of a substantially cylindrical matrix of relatively 5 fusible metal having flat opposite ends, with two bodies of Hertzian-Wave-detecting crystals imbedded in said matrix having sensitive wave rectifying surfaces exposed on the opposite fiat faces of said matrix re spectively 10 In testimony whereof I uflix my signature.

ALBERT LOPPAGKER. 

